Feat: Retries persistence (#3814)

* Feat: Retries persistence

* Fix: Set duration for first beat of push monitor

* Feat: Update UptimeCalculator in push route

* Fix: Handle resend in push route

* Chore: Remove debug log

db/knex_migrations/2023-09-29-0000-heartbeat-retires.js

@@ -0,0 +1,15 @@
+exports.up = function (knex) {
+    // Add new column heartbeat.retries
+    return knex.schema
+        .alterTable("heartbeat", function (table) {
+            table.integer("retries").notNullable().defaultTo(0);
+        });
+
+};
+
+exports.down = function (knex) {
+    return knex.schema
+        .alterTable("heartbeat", function (table) {
+            table.dropColumn("retries");
+        });
+};